Can straightener and method



A.J.MARCHESE CAN STRAIGHTENER AND METHOD Original Filed April 22, 1935 Oct. 8, 1940.

Patented Oct. 8, 1940 UNITED "STATES PATENT OFFICE Canfix Corporation, fornia a corporation of Cali- Application April 22, 1935, Serial No. 17,663 Renewed January 3, 1940 12 Claims.

This invention relates to can straightening mechanisms, and is particularly directed to the straightening of the side walls of dented cans which have both the upper and lower flanges or beads in position, as in the case of filled cans.

In canning practice a large number of cans to which the tops have been applied become badly dented, thereby interfering with the application of labels and at the same time producing unsightly goods which will not bring the best prices. Since both tops and bottoms have been applied, these cans cannot be rolled internally.

The object of the present invention is to provide both a method and apparatus for removing dents from cans flanged or beaded at both ends so that the can walls will be substantially restored to their original uniform shape. I have discovered that these ends can be accomplished by engaging or gripping the can ends under the flanges or beads by opposing means engaging under or around the flanges or beads at the opposite ends of the cans, and forcing said opposed means apart. This forcing restores the cans ends to substantial parallelism and results in drawing out the dented portions practically to original position.

The invention therefore may be said to reside in gripping or engaging the ends of'flanged or beaded cans having dented walls and drawing or forcing apart, or otherwise spreading or separating, the portions of the flanges or beads in line with the dents to draw out the dented portions to substantially their original positions. The invention also resides in apparatus comprising means for engaging the ends ofsuch cans and means for forcing apart or separating such engaging means to restore the beads or flanges to substantial parallelism and to draw out the dents thereby. The invention further includes such apparatus having means to limit the-amount of force and/or the amount of expansion or separation and thereby avoid damaging the cans.

In the accompanying drawing wherein certain embodiments of the invention are illustrated by way of example:

Fig. 1 is a side elevation of one form of apparatus holding a dented can in position ready for straightening Fig. 2 is a fragmentary elevation showing the relation of the can and the flange engaging means after straightening;

Fig. 3 is a plan view showing the relation of the parts in can engaging position as taken from 5 the line 3-3 of Fig. 1; and

Fig. 4 is an elevational detail taken from the line 4-4 of Fig. 1.

In the drawing the cans C to be straightened is shown in Fig. 1 as having a deep dent on the right side. Dents act to draw the beads or flanges B of the can together onthe side in line with the dent, as illustrated. Straightening consists in forcing the beads B apart so as to restore approximately the original parallelism of the beads, and this results in drawing out the dent to approximate the original smooth surface, as il lustrated in Fig. 2.

To accomplish this result, straightening or spreader plates [0 are engaged under the upper bead or flange B of the can, and lower straighti" ening or spreader plates l2 ar engaged with the bead B on the lower end of the can. Each of these plates Ill and I2 is provided with a semicircular opening to engage around one half of the circular can wall. In order to retain the relationship of the parts and prevent any tipping of these engaging plates, the ends of the plates 10 are set upon spanner bars l4, while the. lower plates I2 engage onthe under sides of spanner bars l5. Both pairs of spanner bars l4 and [5 are provided with reinforcing ribs l6, and preferably the engaging faces of these bars are provided with positioning studs l8 which engage somewhat loosely. in corresponding apertures in the plates In and I2 and prevent the latter from shifting.

In order to assemble the parts as a unit, and to provide for actuation, the spanner bars 15 are carried on a yoke 20 integrally or otherwise secured thereto. On the upper side of the middle of each bar l5, a pressure-fluid cylinder 22 is mounted. From the upper end of each cylinder a piston rod 24 projects, the upper end thereof being secured to the under side of the respective spanner bar 14. The lower end of each piston rod 24 carries a piston 25 working in the cylinder 22 under the influence of fluid pressure, preferably hydraulic fluid pressure,' supplied to the two cylinders through fluid-pressure lines 26. The pressure to the lines 26 is supplied through a pressure regulator R from a high pressure line 21, the regulator having connection with lines 26 through a control line 28.

When pressure is admitted to the cylinders 22, it forces the pistons 25 upward, thereby tending to force the upper spreader or straightening plates Ill away from the lower plates l2. In order that the pressure may not exceed the strength of the beads or flanges B of a normal can, the pressure regulator R is employed. In

order to limit the stroke of the pistons beyond any predetermined maximum, especially beyond that point where a weak bead or flange begins to give away, each cylinder 22 is provided with an up-standing stroke-limiting bracket 30, the bend or transverse connecting portion of which is adapted to be engaged by a stroke limiting stop 32 secured in position as by means of a set screw 33.

In operation, the pistons 25, piston rods 24 and upper spanner bars M are lowered by release of fluid pressure in cylinders 22, and the spreader plates If! and i2 are disengaged from the positioning studs l8. A dented can C is then moved into position between the rods 24 and spanner bars M and l 5, the can resting on yoke 20. The lower spreader plates l2 are then moved in from opposite sides into engagement with the walls of the can and the upper edge of the bead B, and they and the can are raised into position so that the studs H3 engage in the corresponding apertures in said plates l2. This relation may be maintained by slipping a wedge W or the like in between the can bottom and the yoke 28. Upper spreader plates iii are then placed on the upper spanner bars M as to engage around the sides of the can C under the bead B and to engage over studs l8. Preferably the can C is set so that the deepest part of the dent is opposite one of the piston rods 24 and its spanner bars 14 and I5. Pressure is then admitted to the cylinders 22, forcing up the pistons 25, rods 24, bars !4 and plates it. When the plates iil'engage under the bead B of the sloping can top, they will first assume the sloping position of the can top, as shown in Fig. 1. Since the pressure of the fluid is less than the strength of the joints at the beads, the piston at the left will cease to move upward.

However, on the right side the pressure to raise the right side of the bead and draw out the dent is less than the fluid pressure applied. Therefore, the right piston rod 24 and spanner bar.

[4 will move up until the dent is substantially straightened out, as indicated in Fig. 2, whereupon with a normal can all movement ceases. The can is then removed by release of pressure in cylinders 22 and reversal of operations. The dent is so completely removed in most instances that the can may be labeled, packed and sold as readily as though never dented. Also labeled cans which have become dented can be straightened with this device.

However, should the can have become weakened at the flange so that it will not withstand the pressure necessary to straighten out the dent, then the engagement of the stops 32 against the tops of the brackets 30 will prevent ripping off the top or bottom of the can.- Thus means are provided both for limiting the pressure so that a normal can will not be damaged, and for limiting stroke to avoid undue motion as in the case of a weak top or bottom.

It is to be understood that the embodiments here disclosed are merely illustrative of the generic invention, and are not limiting, because many variations including automatic operations and the like may be made within the scope of the appended claims.

I claim:

1. A can straightening machine comprising relatively movable spaced devices having can-endengaging means adapted to be disposed in nonparallel relationship and to be engaged with the opposite ends of a dented can and means for forcing apart said engaging means to return the can ends toward normal position and draw out dents.

2. Apparatus according to claim 1 wherein each spaced device comprises two members having substantially semi-circular engaging parts to engage at the sides of the respective can end, and means to hold said two members in an engaging position.

3. An apparatus according to claim 1 and means to limit the effect of the separating force working upon'said engaging means.

4. A can straightening device for cans having flanges on both ends comprising spaced devices adapted to be disposed out of parallelism to engage under non-parallel flanges on opposite ends of bent cans, means to retain the engaging means in position on said opposite ends, and means to separate said engaging means to spread portions of the opposite ends of said cans for straightening the sides of the cans.

5. Apparatus according to claim 4 and means to limit the separation of said engaging means.

6. A can straightening device comprising means to engage a bead or flange on one end of a bent can, means to engage a bead or flange on the other end of a bent can, means connecting said engaging means for the two ends of the can,

and means associated with said connecting means to separate said engaging means and said beads or flanges to draw out the bent portions toward normal position.

7. Apparatus according to claim 6 wherein the separating means is actuated by pressure, and

means to limit the pressure application.

8. A device according to claim 6 wherein the separating means is hydraulic, and means to limit the hydraulic pressure.

9. A device according to claim 6 wherein the separating means is actuated by fluid pressure, means to limit the pressure applied, and means to limit the stroke of the separating means.

10. A method for removing dents from cans having flanges at the opposite ends thereof, com- 1;.

prising applying engaging means to said flanges and thereby engaging said flanges, applying a force to said engaging means tending to separate said flanges and causing the force to separate the portion of the flanges in line with the dents to draw out said dents and restore the can walls and flanges to approximately the original position.

11. A method for straightening dented side walls of dented metal cans having external flanges at their ends, which comprises applying engaging means to said flanges and causing said means to engage under the inner edges of said flanges, and applying a force to said engaging means tending to separate the flanges and causing the portions of the flanges in line with the 

